<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!-- el的运算符  -->
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%
	String basePath=request.getScheme()+"://"+request.getServerName()+":"+request.getLocalPort()+request.getContextPath()+"/";
	pageContext.setAttribute("str1","");
	pageContext.setAttribute("str3",null);
	pageContext.setAttribute("array",new String[]{});
	pageContext.setAttribute("array1",new String[]{""});
%>

<html>
<head>
<base href="<%=basePath%>"/>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
${empty str1 }
<br></br>
${empty str2 }
<br></br>
${empty str3 }
<br></br>
${empty array }
<br></br>
${empty array1 }

</body>
</html>